Pipe bending tool



Dec. 8, 1931. J. H. BLYTHE 1,835,264

PIPE BENDING TOOL Filed Aug. 21, 1950 Patented Dec. 8, 1931" PATENT mm;

Janus HENRY BLYTHE, OF'VDENVER, COLORADO r11 3 JZBENDINFG 'roor.

Application filed au ust a1, 1930., sa 110 476351;

This invention relates to a device for bending pipe and is more particularly adaptable to the use of electricians in. bending and shaping electric'conduit. fThe principal ob- 5 ject of the invention is to provide a simple, efficient. and easily operated device which will be lightin weight, easily transportable to the job,and which can be secured uponany convenient board; beam; or work bench. Other objects of the invention are To provide adjustments for accommodating the most used diameters or sizes of con duits; fv To provide an adjustable stop so that the device'will be automatically stopped when it has formed a 90 bend; I

To provide a simple and positive locking mechanism for locking the conduit against the bending sector;

that it will accommodate variousdiameters of conduit; "f j To provide a double bending sector so that. the conduit may be bent to either of two radii; and i To so'construct the device that the bent conduits may be placed in position or removed throu h the side of the bending sector so as'to ma e it unnecessary'to draw the entire conduit through the device.

'Other objects and advantages reside the detail construction of the invention,

which 'isi'design'ed for ,simplicity, economy,

and efficiency. The's'e will becomemore a'pparent from the following description.

In t following detailed description of the {invention reference is had tofthe' accompanying drawings which form a part hereof. Like numerals ,refer to: like parts in all views of the drawingsfand throughout the description. v

In; the drawings: j r v Fig. 1 isa right side elevation of the device illustratingit in the closed position for carrying or transporting. Y

. Fig. 2 is'a plan view thereof.

Fig. 3 a leftside elevation illustrating the handle and locking device in position ready to-receive a conduit, or pipe to be bent.

- To so construct the locking mechanism.

flanges ofthe base channel 10 and forms a 26 acts to constantly pull the link 23 inwa'rd- 'ly. A finger bail 27 is provided bymeans Fig. 4 is a cross sectiontakerion the line 44 Fig.

Fig. 5 is al'ocking plate.

The invention comprises a base channel 10 provided with suitable openings llby means ofv which it may be secured to any suitable supporting surface. The conduit to be bent is supported within the base channel lOj'upona series of flat rollersj12fand a detail perspective view of the grooved roller'l3x One ofthe rollers 12 is mounted upon 'a'roller shaft 14 upon the extremity of which a b1'acket arm" 15 is hinged. The arm 15 supports at its upper extremity a bearing shaft or'tube 16 upon which, is mounted a sector casting 17 J The casting 17 is provided with a handle socket 18; in which a suitablehandle 19 of any desired length is secured by means of a suitable set screw 20. As illustrated" the casting 17 carries a large bending-"sector 21 and a small bending, sector 22. A grooved track isformed'on each of thesectors 21 and 22 toconform to theexterior surface of the conduit.- i

The free extremityof the arm 15-is sup ported at any desired height bymeans of a link 23.- The link 23 is mountedon the extremity of a shaft 24 that passes through the bearing shaftforone of theroll'ers 12.; 1 The shaft 24 extends through the opposite side of V theiba se channel terminating in a bearing washer- 25 againstwhich a compression spring of which thelink maybe pulled outwardly. The {free extremity of the link 23 carries .a stud'28 which may be placed in any desired one of'a series of stud holes 29 in the armlebracket 30 extends outwardlyat one extremity of the sectors. locking plate 31 is carried by the bracket 30 upon a-pivot shaft 32.: The lockingplate' 31-is provided with notches 41 and 42,fwhich co-act'with the grooves inthe sectors 22 and 21 respectively to lock or hold the conduit there against. The plate'31 is provided with a hooked extremity 34 which, when: in the closedposition, u

passes over a projection 35 upon the casting 17 to prevent the bracket 30 from being bent or being forced outwardly by the reaction of the conduit being bent.

A notched adaptor block 44: is provided, which is pivoted upon a pin 36 in the plate 31. The block 44 can be swung into and out of position in the notch 42 to reduce the diameter thereof so as to clamp a smaller diameter conduit.

It is desirable to have some means for limiting the possible length of the stroke of the handle at times so as to form exact 90 bends.

This is accomplished. by means of anadjust-- able stop 37 which is slidably mounted upon a supporting pin 38 on the inner face of the arm l5-and which contacts with a stop lug 39 upon the handle socket 18.

The stop 37 contains a slotted opening 33, that allows it to slide upon the pin 38. The slotted opening is not positioned in the exact longitudinal center of the stop so that the handle can be stopped at two diiferent points by turning alternate extremities of the stop 37 upward. I

Let usassume t-hatitis desired to form a small radius bend. in a. length of conduit. The stud of the link 23 is passed in the upper hole 29, as shown in Fig. 3,. to bring the sectorsv to the lowest position. The conduit. is then positioned, as shownin broken line in Fig. 3, andthe; locking. plate is closed sothat its upper notch 41: will contact with the conduit. The longer extremity ofthe stop 37 is turned upwardly as shown in Fig. 3. The handle 19 is. now swung downwardly until the lug 39 contacts with the stop 37. This will form a 90 bend inthe conduit. The handle is then returned to its former posi tion which will automatically throw the locking plate to the open position of Fig. 3 and release the conduit.

To form a large radius bend-in large conduit the link 23 is placed inthe lowermost hole 29 to raise the sectors. The conduit is placed under the large sector 21 and the locking. plate is closed with the adaptor 44 in the solid line positionof 5. This brings the notch 42 into contact with the conduit securely lockingit in place. The stop 37 is reversed end to endso as to bring its shorter extremity uppermost and the. handle 39 is closed to contact with the stop. v

If asmall conduit isto bev bent to the large radius-the above operation is employed except that the adaptor 44 is swung to the broken line position of 5 so as to partially close the notch 42 to allow it to grip the small.- er conduit and the link 23 is positioned in the middle hole 29 tobring the sectors into proper relation tothe base channel.

It is desired to call attention to the fact that when bending, the pull upon the conduit tends toforce the locking plate 31 outwardly so asto exert a: bending strain upon the bracket 30.. This strain, however, is absorbed by the hooked extremity 34 which engages the projection 35 and prevents the bracket from being forced outwardly. There is also an excessive downward pull upon the locking plate 31 but this is not transmitted to the pivot shaft or pin 32 since the extremity of the locking plate rests in a groove in the bracket 30, shown at 43,. Fig. 3.

When not in use or in carrying the device from one job to another the stop member 37 is turned sidewardly as shown in Fig. 1 to allow the handle to be brought parallel to the base channel 10. The handle 19 is then socured to the base channel 10 by means of a suitable chain 40, and serves as a suitable grip for carrying. the device.

The side walls of the two sectors are cut away at the upper extremity as shown at so that whenthe handle is in the position of Fig.

3 the conduit can be removedfrom the de- 4 vice or placed therein through the sides of the sectors, thus making it unnecessary to passthe entire length of conduit under the bending sectors or to release the link 23 if it is desired to place or remove a conduit length.

W hile a specific form of the improvement has been described and illustrated herein, it is desired to be understood that the same may be varied, within the scope of the appended claims without departing from the spirit of the invention.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent i 1. A pipe bending device comprising: a base member; a bearing arm pivotally secured at one side of said base member; a bearing shaft supported by said bearing arm; a bending sector mounted upon said bearing shaft; means for locking a pipe at one extremity of said sector; and means for securing said sector at any desired elevation above said base member.

2. A pipe bending device comprising: a base member; a bearing arm pivotally secured at one side of said base member; a bearing shaft supported by said bearing arm; a bending sector mounted upon said bearing shaft; means for locking a pipeat one extremity of. said sector; means for securing said sector at any desired elevation above said base member, said sector comprising: a plurality of arcuate tracks of differing diameters.

3. A pipe bending device comprising: a base member; a bearing arm pivotally secured at one side of said base member; a bearing shaft supported by said bearing arm a bending sector mounted upon said bearing shaft; means for locking a pipe at one extremity of said sector; means for securing said sector at any desired elevation above said base member; said locking means comprising: a. hinged plate adapted to swing against the pipe at one extremity of said sector.

4. A pipe bending device comprising: 7 a base member a bearing arm plvotally secured at one side of said base member; a bearingshaft supported by said bearing arm; a bending sea tor mounted upon said bearing shaft; means for looking a pipe at one extremity of said sector; means for securing said sector at any desired elevation above said base member; sa1d locking means comprising a hmged '5. A pipe bending device comprising; a

' base member a bearing arm pivotally secured at one side of said base member; a bearing shaft supported by said bearing arms a bending sector mounted upon said bearing shaft; means for looking a pipe atone extremity of said sector; means for securing said sector at any desired elevation above said base member said lockingmeans comprising a hinged plate adapted to swing against the pipe at one extremity of said sector; and an adaptor member'incorporated in said plate so .as to adapt it to contact with differing diameters of p p a 6. A pipe bending device comprising: a base member a bearing arm pivotally secured at one side of said base member; a. bearing shaft supported by said bearing arm; a bend-' ing sector mounted upon said bearing shaft; means for looking a pipe at one extremity of said sector; means for securing said sector at any desired elevation above said base member; and a stop arranged to limit the bending movement-of said sector.

7 A. pipe bending device comprising: a base member a bearing arm pivotally secured at one side of said base member; a'bearing shaft supported by said bearing arm; a bending sector mounted upon said bearing shaft;

means for looking a pipe at one extremity of said sector; means for securing said sector at any desired elevation above said basememher; a stop arranged to limit the bending movement of said sector; and means for adjusting said stop so that it will limit said movement to a desired arc.

8. A pipebending device comprising; a.

base channel; roller shafts carried in said base channel; rollers mounted on said shafts;

a bearing arm hinged upon one of said shafts and extending above said base channel; a

bending sector member journaled, on said 7 bearing arm and arranged to sw ngover said base channel; a link pivoted on another of a bearing arm hinged upon'one of said shafts and extending above said base channel; a bending sector member journaled on said bearing arm and arrangedto swing over said base channel; a link pivoted on another of u said shafts; a projection on said link adapted to engage openings in said bearing arm so as to support said sector at any desired elevation; and aspring acting to force said projection into said openings.

10. A pipe bending device comprising: a

base channel; roller shafts carried in said base channel; rollers mounted on said shafts; a bearing arm hinged upon one of said shafts and extending above said base channel; a bending sector member journaled on said bearing arm and arranged to swing over said base channel; a link pivoted on another of said shafts; a projection on said link adapted to engage openings in said bearing arm so asto support said sector at any desired elevation; and a stop member carried by said bearlng arm and arranged to hunt the movement of said sector member. 7

11. A pipe bending device comprising: a base channel; roller shafts carried in said base channel; rollers mounted on said shafts;

a bearing arm hinged upon one of said shafts and'extending above said base channel; a bending sector member journaled on said bearing arm and arranged to swing over said base channel; a link pivoted on another of said shafts; a projection on said link adapted to engage openingsin said bearing arm so as to support said sector at any desired elevation; a bracket extending beyond the arc of said sector; a locking plate hinged in said bracket so as to swing toward said sector and look a pipe against one extremity thereof. I

In testimony-whereof, I affix my signature.

JAMES HENRY BLYTHE.

said shafts; a projection on said link adapted 7 to engage openings in said bearing arm so 7 as to support said sector at any desired elevation.

'9. A pipe bending device comprisingzja base channel; roller shafts carried in said base channel; rollers mounted on said shafts; 

